I don't know if anybody is aware of this fact but SACD contains less
information per track than a Red Book CD!
The bitstream contained in SACD can be at least 6 times smaller without any
loss of information.
I haven't seen this anywhere in the internet but here is the idea of
encoding: assume your previous bit in the bitstream was 1 then if the
following bit is 1 the output signal increase should be twice as much as the
previos increase of the signal. Othewise, if the following bit is 0 then
output signal should be increased two times less than the previous increase
unless the previos output value was 1 in this case the following output
value gain should change the sign ( polarity ).
Using this encoding technique an equivalent of SACD track can be encoded to
take up the size 37% less than the track of a CD. Or vice versa: with the
size of SACD track the information that can be stored will have resolution
of 32 bit at 20 KHz ( vs. 6 bit in SACD )
I wish somebody decides to release records of such a high resolution

"Alex Zhyk" wrote in message


I don't know if anybody is aware of this fact but SACD contains less
information per track than a Red Book CD!

I think this came up when the format was first announced. Isn't the gotcha
that you're comparing the bitrate of one SACD channel to two channels of Red
Book CD?

The bitstream contained in SACD can be at least 6 times smaller
without any loss of information.

Well, some information is lost with SACD. What SACD does is vastly
compromise the SNR above 20 KHz. This is a good thing to do
psychoacoustically speaking, but SACD doesn't go far enough. There's simply
no need to reproduce sound 20 KHz because people can't hear the difference
when it is absent or present.